Ordnance breech mechanism



A. T. DAWSON El AL ORDNANGE BREECH MEGHANISI Deg. 18, 192&

Filed Sept. 5, 1926 5 Sheets-Sheet w r o a w mm m MT .7 $10., 4 H. H M. W

Dec. 18, 1928. 1,695,728

A.- T. DAWSON ET AL ORDNANCE BREECH MECHANISM Filec l sept. s, 1926 s Sheets-Sheet 3 Geor yemmai'i Dec. 18,1928.

A. T. DAWSON ET AL ORDNANCE BREECH MECHANISM Filed Sept. 1926 5 Sheets-Sheet 4 CZrZkur f'zez/orflawon 1,695,728 A. T. DAWSON Er AL ORDNANCE BREECH MECHANISM Dec. 18, 1928.

Filed Sept. 1926' fivvsivm s miurfmu'ormwsow izya GeoIyeZVzomaSBLK/WQI Q @a/ fly A W Patenied Decaf 18,- 1928;

iAnmj -ifin m nflvajbaws mgrjmib "the piSfiQIl TOd' 'tO 'Wi V olp'e'r'i position; the 1m 7 V ,ti'vej engagment with 17' rie-r sol as to prevnt th -said-'angu1a 'x1is- ""3 6 Sa d;

Q'pferat'e to prevent: angular displacemm 0f during "the swingingzmvemen t's bf 'th ear V being-in theclosed position. 7

in position by a spring plunger which; en

gages in the holepreviously occupied by the crank pin by which the first of the aforesaid f short links was connected wtQ the operating crank shaft. 3 This arrangement prevents the power gear and'the hand lever frombein coupled to the operating crank D she-n1 at thesamjetimel a J j In order that the said inventionemay be clearly; understood and? readily gcarriediinto effect, the same willnow be described more fully with reference totheuacconipanying draw1ngs,-in. which Figure 1 is a rear'elevation of a gunprovid'efdwith breech mechanism in accordance with-this invention, the breech mechanism Figure 2 isa plan'of Figurel, f

r I Figure 3 ls a sectional side elevatioi'i jot Figure 1 viewed "from the right hand side of the latter figure, V-

Figure 4 is a section taken approximately on the line A, t of Figure 3;

Figure 5 isa section taken approximately on the line 5, 5 of'Flgure 4E; Y

e Figure 6 is arview s imilar to "l igurc 3 shewing tllGlDOSltlQIl of the partsuwhen the breech screw is-unlocked and before the carrier is swung out, it beingjassumed for the purpose of il'lustratingtheparts more clearly} that the carrier'has not receivedthe usual'smalll'opening movement under the lnfluence of the. afQIFBSflldCZLHldQVlCfi, j

F gure"? 1s a-vlew similar to*F1gure ,8

shwing the breech mechanismein the fully.

7 open positione this figurebeingnrawn on asmaller scale than Figures 1 to 6, p

t Figure Sis a plan of Figurej'i, V V

Figure9isa view similarto Figure l but with parts in :SGC tlOIIQ ODFtil 1lne-"9i 9 of Fig 2',

Figure 10 1s a side elevation of; Figure 9 viewed from the. right, Figui-es 9 and 10 showing the parts in .conditiQnffor 'hand' operation of the breechlnechanism,

Figure 11 is arsecti'on taken :opprokimately on theline 11, ll otFigure 10. I I 'K Figure 12 is arsectionitaken,approximately on the line 12,12 of Figure 11,

Figure' lli is'asection taken approximately 'onthe line 13'; 13iofF1gure 12,

' Figure I l-is a view similar to Figure 13 7 but she'wing the parts'in the positionthey f occupy when the breech screw is unlocked and the b'reech'inechanism is swinging out,

' -Figure 15 is a localsection taken on the line 15, 15 of Figure 14; r 1

V A is the breech i s -pthesim, B the breech screw, C the cariierandC the'hinge spigot of the said carriery D is the transverse Operating" crank shaft mountedini the 'carrier, D is the crank pin on the outer end of this operatingcrankshaft; 'D is the breech. screw actuating crank pin on the {yea-m1 pivot p1 W p e e latter link 15 connect'ed by a vertical pivot inner end" of the said-shaft, the latter pin serving to operate the breech screw in a similar manner to that described and shown in the specification and drawings of British Patent No. 6739 0f19l2. A

' E'is theoperating cylinder and E is'the piston disposed inthis cylinder, the said cylinderbeing attached longitudinally tothe gun at the same side as andslightly-in-front of the carrier hinge spigot'a'n d the rod 0 of the pistonE projecting through the front endjof the cylinder where it is" connected to V the front end of a bar sl ding 1n guides on the cylinder E. 1 The rear end ofthe said baris connected by a'horizontal pivot pin 6 to a short link E? hich' is connected by a e. 0 a'longer link E. The

pin e to anotherishortl link E thc'rear end of which engages with the aforesaid crank pin D on theouterend ofi the' transverse" operating crank shaft 1). This arrangement of links provides the g'neeessary universal joint connections to accommodate the angular movementsiof the crank. pin D "andthe swinging movements of the'carrier C during the OperatiOnof'the breech mechanism. C

is the aforesaid projection on thejcarrier this projection" having a recess into which the J piston E completes the swinging out'movement of the carrier through the intermediary oi the link F) and the stop C The'fully "swung-out position ofiithe' breech; mechanisnr lsshown by F gures -7' and. The s'w-1ng1ng-1n movement of the carrier 13 effected; by the-rearward movement of the piston El, whichinove nent is transmitted to the carrier by means of the link E rwhich at I this time bears against the inner "wall of the recess in the projection C? and th s position is maintained until'th ebreech screw Com- E lnences to move toits'locking' position under the influence of the aforesaid caindeviceF, F As the said projection (Prices notope rfate to prevent angular displacement of the breech screw towards .its locking position "during the swinging movements of the car:

rier a latch or catch G is provided for co-opcrating with an armor projection D moving with] the operating crank shaft D during the swinging movements'fof the carrier so as; Jtopreventthe said angular Cl1SPlIQ6II1QIlt of the breech screw. This latch. or catch is moved into and out of, its operative position at the correct'times in relation to the operations of the cam dev1ceZF,F by means of a cam' groove 0; formedin a braeketprojecting from the breech end of the gun between Ill) ' othe-hinselags"ihersan arallsistratify-r V h t l I that as the cylinder'occupies a fixed position til th s id la ehlor at-chic acme; m

roo e This operat c in aid the rank pimp? is' rtanged t ly at its dead centre position v eech sc ew tal yiuale ks a nglfi urefi- The cylinderE and its associated parts are shewn as being constructed generallyin the manner'described in the specification of prienters the cylinder to efiect' the closing movementiof the breechmechanism isjformed in. the cylinder wall,this port being ,provided on the gun the pressure fluid connections E", E are of a simple character in comparison wlt-h the swivelhng connect ons necessary in those COI1Sl31L1Ct1OIlS'lIl which a pivoted cylinder is employed.

For" hand operation of l nism thev aforesaid 0111111113111 D lSIQIIlOYBCl as is also the aforesaid horizontalpiv'ot pin fitted with a spring-controlled catch H? and retains the handlever in the locked po-fl e and the unit composed of the links E E and is connected to the sliding bar Ei'by means of lugs c e on thesidethereof through which lugs and through the holes inthe links EKE the pin'sre' fandcl) are passed as shewn inFigure10, it being unv derstood that to effect this connection the unit composed of the said links is moved I about its longitudinal aXis'through-a right" angle. In the position shewn by Figure 10 a projection e on the link E e'ngages-between two lugs e, e on the cylinder E and thereby locks the piston E to the cylinder.' A handlever H is'then inserted in a-n'undercut guide D? in 't-heouter end ofrithe; operat ing crankshaft D andls secured n 13081131011 by meansof a spring plunge-r 11 whichen-r gages in the hole previously occupied by the .crank pin D this arrangement preventing the power gearand the handlever from being coupled to the operatingj crank shaft 'D at the same time. The said handlever' is which engages with a stop C on thecarrier sitionj until released by the hand when the handle ofthe said handlever is'grasped in I order to openthe breech mechanism, "it be jing seen from Figures 9 and lO'that this catch is moved downwards by-.downw-ard movement of the hand upon the' said handle.

Apart D of the guide D co-operates with theaforesaid stop C to limit the; locking-i. movement of the shaft D whether the latter is being operated by power or by the handlever H and the; latter has aprojection "on Saidfsh'aft;alprojectiononth'e' carriert andfa-Yswingingllink m h i the breech mecha- "to openposition. v

claim.2fwhere in' the link mechanismflcom f v.il s aa mounted on the V 0 mar, atrans erse Vb screwoperating shaft mounted-in the caf rier, a cylinder and piston attached longi or British Patent No. 205522 with reference'j to the carrier-swinging cylinder,.except'that the port 6 through which the pressure fluid j V V fnism through which thepistOn rod of said tudinally to the gun on the same side as and; 1} forward of the carrierihinge, a ,crank' pin" I onsaid shaft,and"a swinging link gmecha piston isj'connected to; the'crank 'pinqk 2. 'In power operatedj breech mechanisn forguns, a hinged carrier, a bre chsmiew; mounted on the carrier, atransverse};breech 1; i

screw operating shaft mounted inthe car i -rier,i;a "cylinder and piston attached Vlon'gi-f;

tudinally to the gunonthe same side as ancij forward of'the carrier hinge; a crank pin, '1

ing y moveinent' oft-said piston, l will'jact a ainst said. projection .tocswing the carrier 1 r 3. In; .breeclr mechanism for guns', a hinged;carrier abreech "screw mounted on thecarrier,a transversebreech screw foper ating shaft mou'nted in the.carrierymeansa for rotating such shaft and swinging the 2 carrier, and amovable' latch onthe carrier coactinggviwhen the breech; screw fully v unlocked with a projection on the shaft; to'f, prevent angular displacementjof'the; breechi1 screw during-- swinging movements of itlie carrienm V 3 A 1103-". 4. Ordnance V breech mechanism as -in V claim-.3,-wherein the latcli','is moved ma ma; out of coacting re lationlwith the projection onthe'jbreechscrewoperatingshafflat the T 'a correct; times by. a. cam groo ve formed'lina bracketon the breech e d-iof-the gunfl j Ordnance breech mechanismfas' inT claim 3, whereinthecrank pin onthje breechscrew, operating .cr'a'nk :shaftis' arranged. to be nearly at its "dead center position when th'e breechi screw is' fully unlocked forpthe ,f:

g 6.- Ordnance breech mechanism fiasl" inf v prises i addition to the shortlink twoji 2 other l nks interposed between the saidfl short'link and 'a 'slicling bar which extends to thefront of the/operating cylinder where i inder, s' ubstantially'a's described; 1

f7. Ordnance breech mechanism: as in' clalm 1, whereln ZEOR hancl operatlon 0f the bfe'ch inehanism the swinging link mchanism is unc'o u pledl frpin fih breech "screw operat lng crank sha ftnnd 72p hand lever 1's :Mafaicliepl to; th e' ufe r enci 6f said shaft and is' secured in position by a; spring plunger which engages in the holepreviouslyoccupied the crank pinfconne'eting the" link mjechanisfin t o-lthef said shaft 'for the pu'r- ARTHUR TREVOR DAWSON. GEORQE' THOMAS J BUOKHAM. 

